CN107579332B - Synchronous expansion and contraction cylindrical surface antenna based on Bennett mechanism - Google Patents

Abstract

The invention discloses a synchronously unfolding and retracting cylindrical surface antenna based on a Bennett mechanism, which can be unfolded to a designated configuration for work, and can also be folded for easy transportation. The device mainly includes a deployment mechanism, a quick lock mechanism, and a rope drive mechanism. The mechanism deployment mechanism is composed of a connecting rod and a rotating joint. The quick-lock mechanism is installed on the deployment mechanism in an orderly manner, and the rope driving device is sequentially fixed on the deployment mechanism to realize the deployment and locking of the mechanism. When folded, the link of the mechanism is driven by the connecting joint to fold into a bundle around the axis of the joint; when unfolded, the link rotates around the axis of the joint, unfolds to the specified cylindrical surface, and realizes automatic locking. At the same time, the locking rope is opened and locked to realize the repeated folding and unfolding of the mechanism. The invention can realize the unfolding and folding of the mechanism with a single degree of freedom, and has the advantages of small occupied space, reusability, cost saving and the like.

Description

A Synchronous Telescopic Cylindrical Antenna Based on Bennett Mechanism

technical field

The invention relates to a synchronous expansion and retraction cylindrical antenna based on a Bennett mechanism, belonging to the technical field of machinery.

Background technique

In aerospace technology, due to the limitation of the geometric size of the payload compartment of the vehicle, spacecraft such as satellites and space stations widely use expandable mechanisms to meet actual needs by changing their physical shape and size. Compared with the general mechanism, the expandable mechanism has the advantages of simple and quick operation, less space in the fully folded state, reusable, convenient transportation and storage, etc. With the in-depth development of the aerospace industry, the space deployable mechanism is developing in the direction of large-diameter, high-precision, and light-weight, which requires the antenna structure to have a large storage rate and excellent deployment performance.

Most of the existing deployable mechanisms are composed of scissor mechanisms. The rods can be gathered into a bundle and expanded to different shapes. The typical representative of large-scale space deployable mechanisms composed of scissor mechanisms is the ETS-VIII satellite using hexagonal modules. , CSPDA annular truss-type deployment antenna connects the inner and outer two layers of shear units, while Astro Mesh antenna utilizes the characteristics of quadrilateral structural units to expand and contract diagonally.

In order to obtain higher strength and extension-to-retract ratio of the expandable mechanism, the space over-constrained element mechanism has been widely used in its design. A series of retractable mechanisms have been designed based on Sarrus, Bricard, Mayard and Bennettd unit mechanisms.

In recent years, deployable cylindrical structures have been widely used in space applications. The cylindrical surface has the characteristics of strong directivity, high gain, and easy automatic scanning of the beam, and has become an important development direction of the space-expandable antenna surface.

SUMMARY OF THE INVENTION

The purpose of the present invention is to use the unit mechanism to design a new type of cylindrical surface unfolding antenna, which is simple to assemble, can be reused, saves cost, and has high storage rate and surface accuracy.

In view of the above purpose and the current technical background, the cylindrical antenna device with the function of repeated deployment and retraction of the present invention has synchronization, and can realize repeated deployment and retraction, making the overall structure of the device more compact and saving space.

The technical idea of the present invention is to combine the space over-constrained Bennett unit mechanism with the scissor mechanism, and realize the single-degree-of-freedom synchronous deployment of each moving unit of the mechanism in the form of joint connection. The working surface of the antenna device fits a cylindrical surface, and With all the rods it can be compactly folded into a bundle. The entire antenna includes:

The deployment mechanism, the quick lock mechanism, the rope drive mechanism, and the deployment mechanism are composed of connecting rods and rotating joints, which are used as the main frame of the antenna to form the required cylindrical surface shape.

The unfolding mechanism includes m large Bennett unfolding units and m+1 small Bennett unfolding units, these unfolding units are connected in sequence to form the skeleton of the unfolding mechanism, m≥2;

Each large Bennett deployment unit includes four long rods and two torsion spring hinge joints, each small Bennett deployment unit includes four short rods and two rotating joints, and a set of scissor units is between the large and small Bennett mechanisms connect;

Each scissor unit includes a front long rod, a rear long rod, a front short rod, a rear short rod, a front long rod joint, a rear long rod joint, a front short rod joint, a rear short rod joint, The front long rod and the rear short rod are respectively connected with the shaft sleeve hinge through the front long rod joint and the rear short rod joint, and the front long rod and the rear short rod rotate around the shaft sleeve hinge, and the rear long rod and the front short rod pass through the rear The long rod joint and the front short rod joint are connected with the synchronous hinge. During the movement, the synchronous hinge rotates coaxially and synchronously with the shaft sleeve hinge through the shaft pin, and the two have a common rotation range. Two synchronous hinge rotating shafts are located on both sides of the shaft sleeve hinge rotating shaft, which can realize the synchronous rotation of the front short rod and the rear long rod.

The above-mentioned deployable cylindrical antenna has a driving torsion spring at the rotating shaft of the torsion spring hinge joint connected by two adjacent long rods in the large Bennett unit mechanism, the left rotating joint is connected with the left hinge, and the right rotating joint is connected with the right hinge. The page is connected, and the joint drives the torsion spring to provide the driving force for the deployment of the antenna.

For the rotating joints of adjacent rods in the above-mentioned deployable cylindrical antenna unit mechanism, the front contact of the rotating joint is connected with the rotating joint through a screw, and the rear connecting point is connected with the long rod/short rod through a pin.

The torsion spring hinge joints of the adjacent rods in the above-mentioned large Bennett unit mechanism are internally installed with a quick-lock mechanism. The quick-lock mechanism is installed on the deployment mechanism in an orderly manner, and the rope drive device is sequentially fixed on the deployment mechanism to realize the complete deployment of the mechanism. expansion and locking.

Each of the above two scissor units is connected by four long rods and two torsion spring hinge joints to form a large space quadrilateral, and each two scissor joints are connected by four short rods and two torsion spring hinge joints to form a space Small quadrilaterals, and each space is large, the small quadrilaterals are connected by scissor joints and distributed at intervals, forming a folding device that can be folded and unfolded.

The above-mentioned quick locking method adopts the bayonet positioning and locking mechanism. During the unfolding process, the connecting rod drives the lock bolt base connected to the left joint to move, and pushes the cylindrical bayonet on the fixed lock bolt into the locking block. In the guide groove, the limit slider placed in the lock seat at the same time is pushed up due to the entry of the bayonet. After the bayonet passes, the limit slide is reset under the action of the internal compression spring. At this time, the bayonet is positioned and locked in place. In the guide groove, the left limit slider restricts the right movement of the bayonet, and the right compression spring provides a pressure to the left, which restricts the bayonet, that is, the left joint, from continuing to move to the right, so as to realize the quick locking of the lock bolt. During the unlocking process, the limit slider is lifted by the continuous cable, and the left limit of the bayonet disappears, so that the bayonet comes out of the guide groove. In practical applications, the position of the groove should be determined first, and the mechanism can be locked to a predetermined deployment configuration through this locking mechanism. The locking and unlocking process is reliable and easy to operate. The compression spring in the locking mechanism, as an energy storage element, is the reset and power source of the cylindrical bayonet and the limit slider, and at the same time provides the locking force for the positioning of the lock bolt.

When folded, the link of the mechanism is driven by the connecting joint to fold into a bundle around the axis of the joint; when unfolded, the link rotates around the axis of the joint, unfolds to the specified cylindrical surface, and realizes automatic locking. At the same time, the lock is opened and locked by the unlocking rope to realize the repeated folding and unfolding of the mechanism.

The rope driving device includes an unfolding rope and a retracting rope, which are installed on the joints of the unfolding mechanism through a pulley block. The unfolding pulleys are mainly distributed on the outer joints of the unit mechanism, and the non-scissor joints inside the unit Bennett mechanism are distributed with the unfolding pulley block. The tuck ropes are connected sequentially along the unilateral joint. The retracting pulleys are distributed on each joint, and the retracting ropes are distributed in a "Z" shape in the unfolding mechanism.

The advantages of the present invention are:

(1) A cylindrical expandable antenna is designed based on the Bennett unit combination. The working surface of the mechanism can fit the cylindrical surface, and has a folded configuration in which all the rods can be compactly folded into a bundle, and the storage rate is high;

(2) The over-constrained unit Bennett mechanism is used as a unit mechanism, and the expansion and contraction of the mechanism is realized through a certain combination method, and the fitting surface of the mechanism in the collapsed state is a cylindrical surface to ensure that the mechanism has a strong rigidity performance;

(3) The new cylindrical antenna of this design has a single degree of freedom, and the synchronous deployment of each unit mechanism can be realized by providing one drive.

Description of drawings

Fig. 1 is the structural representation of the present invention's synchronous expansion and retraction cylindrical antenna;

FIG. 2 is a schematic diagram of the structure of the Bennett unit of the synchronously expanding and contracting cylindrical antenna according to the present invention;

3 is a schematic structural diagram of the scissor unit of the synchronously expanding and retracting cylindrical antenna according to the present invention;

4 is a schematic diagram of the internal joint connection of the synchronously retractable cylindrical antenna unit of the present invention;

Fig. 5 is the schematic diagram of the quick locking mechanism of the synchronously expanding and retracting cylindrical antenna according to the present invention;

FIG. 6 is a detailed schematic diagram of the quick-locking mechanism of the synchronously unfolding and retracting cylindrical antenna according to the present invention;

FIG. 7 is a schematic diagram of retracting the synchronous retracting cylindrical antenna according to the present invention.

In the picture:

1- Unfolding mechanism; 2- Quick lock mechanism; 3- Unfolding rope; 4- Retracting rope

101-connecting rod; 102-swivel joint; 103-torsion spring hinge joint; 104-scissor unit;

301-front long rod; 302-rear long rod; 303-front short rod; 304-rear short rod; 305-front long rod joint; 306-rear long rod joint; 307-rear short rod joint; 308-front short rod Joint; 309-shaft sleeve hinge; 310-synchronized hinge; 311-shaft pin;

401-left long rod; 402-right long rod; 403-rotation joint; 404-drive torsion spring; 405-left rotation joint; 406-left hinge; 407-right rotation joint; 408-right hinge; 409-rotation Joint front joint; 410-screw; 411-rear connection point; 412-pin;

501-Quick lock mechanism; 502-Left joint; 503-Lock base; 504-Right joint; 505-Lock block; 506-Limit slider; 507-Internal compression spring; 508-Right compression spring.

Detailed ways

The present invention will be described in further detail below with reference to the accompanying drawings.

The present invention is a synchronously unfolding and retracting cylindrical surface antenna based on the Bennett mechanism, including a unfolding mechanism 1, a quick-locking mechanism 2, a unfolding cord 3, and a retracting cord 4, as shown in FIG. 1 .

Referring to FIG. 2, the deployment mechanism 1 is composed of a plurality of unit mechanisms, each unit mechanism is connected by a connecting rod 101 and a rotating joint 102, and the plurality of unit mechanisms are sequentially connected to form the main frame of the antenna, and the deployment surface is the desired cylindrical shape. . The unfolding mechanism 1 includes m large Bennett unfolding units and m+1 small Bennett unfolding units, these unfolding units are connected in sequence to form the skeleton of the unfolding mechanism, m≥2. The deployment mechanism is expandable. The design is composed of four large Bennett mechanisms and three small Bennett mechanisms. The incomplete small Bennett mechanism on the outside indicates that the mechanism unit can continue to expand. Each large Bennett deployment unit includes four long rods and Two torsion spring hinge joints 103, each small Bennett deployment unit includes four short rods and two rotating joints, the large and small Bennett mechanisms are connected by a set of scissor units 104.

3, each scissor unit includes a front long rod 301, a rear long rod 302, a front short rod 303, a rear short rod 304, a front long rod joint 305, a rear long rod joint 306, and a front long rod joint 306. A short rod joint 308, a rear short rod joint 307, the front long rod 301 and the rear short rod 304 are respectively connected with the shaft sleeve hinge 309 through the front long rod joint 305 and the rear short rod joint 307, and the front long rod 301 is connected with the rear short rod The rod 304 rotates around the shaft sleeve hinge 309, the rear long rod 302 and the front short rod 303 are respectively connected with the synchronous hinge 310 through the rear long rod joint 306 and the front short rod joint 308, and the synchronous hinge 310 passes through the shaft pin during the movement. 311 and the shaft sleeve hinge 309 rotate coaxially and synchronously, and the two have a common rotation range. The two rotating shafts of the synchronous hinges 310 are located on both sides of the rotating shaft of the sleeve hinge 309 , which can realize the synchronous rotation of the front short rod 303 and the rear long rod 302 .

As shown in Figure 4, the above-mentioned deployable cylindrical antenna has a driving torsion spring 404 at the rotating shaft of the rotating joint 403 connecting the two adjacent left long rods 401 and the right long rod 402 in the large Bennett unit mechanism, and the left rotating joint 405 is connected with the left hinge 406, the right rotating joint 407 is connected with the right hinge 408, and the joint drives the torsion spring to provide driving force for the antenna to unfold.

In the above-mentioned deployable cylindrical antenna unit mechanism, the front contact point 409 of the rotating joint is connected with the rotating joint 403 through the screw 410 , and the rear connecting point 411 is connected with the long rod/short rod through the pin 412 .

Every two scissor units are connected by four long rods and two torsion spring hinge joints to form a large space quadrangle, and every two scissor joints are connected by four short rods and two torsion spring hinge joints to form a small space Quadrilaterals, and each space is large, and the small quadrilaterals are connected by scissor joints and distributed at intervals, forming a folding device that can be folded and unfolded.

A quick-lock mechanism 501 is installed on the inner side of the torsion-spring hinge joint of adjacent rods in the large Bennett unit mechanism shown in FIG. 5 , the quick-lock mechanism 501 is installed on the deployment mechanism in an orderly manner, and the rope drive device is sequentially fixed on the deployment mechanism to realize The retraction and locking of the mechanism when fully extended.

The fast locking method shown is a bayonet positioning locking mechanism. During the unfolding process, the connecting rod drives the locking bolt base 503 connected to the left joint 502 to move, and pushes the cylindrical bayonet on the fixed locking bolt into the connection. In the guide groove of the locking block 505 on the right joint 504, the limit slider 506 placed in the locking block 505 is pushed up due to the entry of the bayonet, and after the bayonet passes, the internal compression spring 507 acts The lower limit slider 506 is reset, at this time the bayonet is positioned and locked in the guide groove, the left limit slide 506 restricts the movement of the right side of the bayonet, and the right compression spring 508 provides pressure to the left, limiting the bayonet that is The left joint continues to move to the right, enabling quick locking of the bolt. During the unlocking process, the limit slider is lifted by the continuous cable, and the left limit of the bayonet disappears, so that the bayonet comes out of the guide groove. In practical applications, the position of the groove should be determined first, and the mechanism can be locked to a predetermined deployment configuration through this locking mechanism. The locking and unlocking process is reliable and easy to operate. The compression spring in the locking mechanism, as an energy storage element, is the reset and power source of the cylindrical bayonet and the limit slider, and at the same time provides the locking force for the positioning of the lock bolt.

The rope driving device includes an unfolding rope and a retracting rope, which are installed on the joints of the unfolding mechanism through a pulley block. The unfolding pulleys are mainly distributed on the outer joints of the unit mechanism, and the non-scissor joints inside the unit Bennett mechanism are distributed with the unfolding pulley block. The tuck ropes are connected sequentially along the unilateral joint. The retracting pulleys are distributed on each joint, and the retracting ropes are distributed in a "Z" shape in the unfolding mechanism.

Claims (1)

1. a synchronously unfolding and retracting cylindrical surface antenna based on Bennett mechanism, is characterized in that, comprises unfolding mechanism, quick locking mechanism and rope drive device: The unfolding mechanism adopts space single-degree-of-freedom unfolding to realize the unfolding and folding of the antenna; The quick lock mechanism includes a lock bolt, a locking block, a compression spring, a limit slider, the lock bolt and the lock block are respectively installed on the deployment mechanism, and the limit slider, the compression spring and the lock block are assembled together, responsible for Locking and positioning of the bolt; The rope driving device includes an unfolding rope and a retracting rope, which are installed on the joint of the unfolding mechanism through a pulley block; The unfolding mechanism includes m large Bennett unfolding units and m+1 small Bennett unfolding units, and the unfolding units are connected in sequence to form the skeleton of the unfolding mechanism, m≥2; Each large Bennett deployment unit includes four long rods and two torsion spring hinge joints, wherein the two long rods are connected by torsion spring hinge joints, and the other two long rods are also connected by torsion spring hinge joints Connection, each small Bennett deployment unit includes four short rods and two rotary joints, wherein the two short rods are connected by rotary joints, and the other two short rods are also connected by rotary joints. In the large Bennett deployment unit The two long rods are connected with the two short rods in the small Bennett deployment mechanism through a scissor unit; Each scissor unit includes a front long rod joint, a rear long rod joint, a front short rod joint, and a rear short rod joint. Let the two long rods in the large Bennett unfolding unit be the front long rod and the rear long rod, and the small The two short rods in the Bennett deployment mechanism are the front short rod and the rear short rod. The front long rod and the rear short rod are respectively connected by the front long rod joint, the rear short rod joint and the shaft sleeve hinge, and the front long rod and the rear short rod are respectively connected. The hinge can rotate around the shaft sleeve. The rear long rod and the front short rod are respectively connected with the synchronous hinge through the rear long rod joint and the front short rod joint. During the movement, the synchronous hinge is coaxial and synchronous with the shaft sleeve hinge through the shaft pin. Rotation, the two have a common rotation range; the two synchronous hinge shafts are located on both sides of the shaft sleeve hinge shaft to realize the synchronous rotation of the front short rod and the rear long rod; Every two scissor joints are connected by four long rods and two torsion spring hinge joints to form a large space quadrilateral, and every two scissor joints are connected by four short rods and two torsion spring hinge joints to form a small space Quadrilaterals, and each large and small quadrilaterals are connected by scissor joints and distributed at intervals, forming a folding device that can be folded and unfolded; There is a driving torsion spring at the rotating shaft of the torsion spring hinge joint connected with two adjacent long rods in the large Bennett unit mechanism, the left rotating joint is connected with the left hinge, the right rotating joint is connected with the right hinge, and the torsion spring is connected with the left hinge. Provide driving force for the deployment of the antenna; A quick-lock mechanism is installed on the inner side of the torsion spring hinge joint of the adjacent rods in the large Bennett unit mechanism; In the quick-locking mechanism, the quick-locking method adopts a bayonet positioning and locking mechanism. During the unfolding process, a group of adjacent long rods in the bennett unit drive the joints to connect with the rods, and the two torsion spring hinge joints are connected to each other. Install the locking bolt base and the locking block on the joint respectively, push the cylindrical bayonet on the locking bolt base into the guide groove of the locking block, and at the same time the limit slider placed in the locking block The entrance of the port is jacked up. After the bayonet passes, the limit slider is reset under the action of the internal compression spring. At this time, the bayonet is positioned and locked in the guide groove, and the left limit slider restricts the right side of the bayonet from moving. , the right compression spring gives a pressure to the left, restricting the bayonet, that is, the left joint to continue to move to the right, so as to realize the fast locking of the lock; During the unlocking process, the retracting rope passes through the round hole on the limit slider, and the limit slider is lifted by pulling the retracting rope, and the left limit of the bayonet disappears, making the bayonet come out from the guide groove; In the rope drive device described above, the non-scissor joints inside the unit Bennett mechanism are distributed with unfolding pulley blocks, the retracting ropes are connected in sequence along the unilateral joints, the retracting pulleys are distributed on each joint, and the retracting ropes are located at the joints. The deployment mechanism is distributed in a "Z" shape.

Images